It should be entierly possible to modulate packet radio using the GPIO hack, however you would probably need a real-time kernel extension to ensure proper trans

It should be entierly possible to modulate packet radio using the GPIO hack, however you would probably need a real-time kernel extension to ensure proper transmission. Decoding is easily possible on the CPU as well, provided you attach soeme RF demodulation circuitry, e.g. to a sound card input.